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Question
Write the formula to find the magnitude of the gravitational force between the earth and an object on the surface of the earth.
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Solution
Let ME be the mass of the Earth and m be the mass of an object on its surface. If R is the radius of the Earth, then according to the universal law of gravitation, the gravitational force (F) acting between the Earth and the object is given by the relation:
F = `(Gm_1m_2)/r^2`
M = mass of the earth.
m = mass of the object.
r = distance between the earth and the object.
G = proportionality constant.
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